One of the most popular anti-aging serums right now at Sephora, Kate Somerville Deep Tissue Repair with Peptide K8 ($150.00, Amazon.com) certainly sounds advanced and enticing, with “peptide K8” and “patented HSC complex” to make skin “youthful, healthy, and fresh.” But what does current research say about the ingredients? Read on to find out…
Palmitoyl oligopeptide: Not my favorite peptide
There are a number of peptides on the market right now (palmitoyl pentapeptide-3, Matrixyl3000® and Argireline®, to name a few) that have been shown in scientific studies to stimulate the production of extracellular matrix proteins, including collagen and fibronectin. These peptides, in effect, make the skin firmer.
However, Kate Somerville Deep Tissue Repair with Peptide K8 contains palmitoyl oligopeptide. What is great about palmitoyl oligopeptide is that it, like other prominent peptides, significantly stimulates collagen production in human fibroblasts, as shown in a 2007 study in Dermatologic Therapy. On the other hand, palmitoyl oligopeptide has been found to down-regulate elastin expression. From one point of view, this is not a bad thing – elastin expression naturally increases with age, but the elastin cross-fibers grow in a less organized pattern than in individuals at a younger age, so down-regulating unorganized elastin expression may keep your elastin fibers from growing in an aged, disorganized pattern.  Yet, products that have been shown to stimulate elastin production (like one of my favorites, Relastin Eye Silk) also increase the firmness of the skin, so down-regulating elastin expression may not be a good thing, either. With that said, if Kate Somerville Deep Tissue Repair with Peptide K8 contained, say, palmitoyl pentapeptide-3 instead of palmitoyl oligopeptide, I’d be an even bigger fan.
Dermaxyl: Proposed to Redirect Cellular Activity and Reduce Facial Contractions
One of the more exciting ingredients in this product is Dermaxyl, which is a combination of C12-15 Alkyl Benzoate, Tribehenin, Ceramide 2, PEG 10 Rapeseed Sterol, and the aforementioned Palmitoyl Oligopeptide. In specific, Dermaxyl has been designed to be a dual-action compound that contains both a matrikine (a peptide that mediates cellular activity) and a compound called Calmosensine (which contains a cutaneous neuromediator to reduce facial contractions).  Dermaxyl has been proposed to help attract cells to sites that need repair and to contribute to reconstruction of the dermis, according to the text The Design and Development of Anti-Aging Formulations.
Unfortunately, while this sounds wonderful in theory, there is a limited amount of research conducted on the compound thus far outside of Sederma, the manufacturing company of Dermaxyl. For instance, although Dermaxyl can attract cells to sites that need repair in the dermis, does it actually get to the dermis following application of a cream like Kate Somerville Deep Tissue Repair with Peptide K8? (Most ingredients in skin care definitely do not get through to the dermis). While Sederma’s studies look great – they can be viewed in PDF format here – I honestly would like Dermaxyl better if there was more non-company affiliated research further substantiating the claims. At any rate, however, Dermaxyl is definitely something I will research more in the future.
Babassu Seed Oil
Babassu seed oil is bound to be doubly popular in upcoming years: not only is it a natural ingredient, but it also contains omega-3 and omega-6, which aid in inflammation and acts as an emollient to the skin. When applied, Babassu seed oil also provides a pleasant, velvety feeling on the skin, which is more appealing than some other occlusive emollients, like glycerin or urea. Bottom line: Look for babassu seed oil in skin care a lot in the future.
Overall Opinions
Kate Somerville Deep Tissue Repair with Peptide K8 is a very hydrating moisturizer. Although it is lightweight, it contains a lot of hydrating ingredients that may make this a better choice for dry or normal/combination skin than oily skin. (As always, consult with your dermatologist before trying this or any other product). It is not likely to aid in treating hyperpigmentation, acne, or rosacea. However, it may aid a bit in the prevention/treatment of wrinkles and in maintaining/increasing skin’s firmness through somewhat increased collagen production.
Overall, I appreciate the hydration and anti-aging ambition of Kate Somerville Deep Tissue Repair with Peptide K8. While I wish that it contained a different peptide and that its Dermaxyl compound had more independent research backing, I think that most customers will find this to be a luxurious “high-tech” indulgence, and I’m willing to bet Kate gets a lot of repeat customers on this one!
Ingredients in Kate Somerville Deep Tissue Repair with Peptide K8
Water, Stearic Acid, Ceteareth-20, Cetearyl Alcohol, Isopropyl Myristate, Isocetyl Stearoyl Stearate, C12-15 Alkyl Benzoate, Glycerin, Cyclopentasiloxane, Dimethicone, Orbignya Oleifera Seed Oil, Caprylic/Capric Triglyceride, Cannabis Sativa Seed Oil, Squalane, Cholesterol, Urea, Sodium PCA, Macadamia Ternifolia Seed Oil, Silk Powder, Simmondsia Chinensis (Jojoba) Seed Oil, Cetyl Alcohol, Triethanolamine, Butylene Glycol, Chlorphenesin, Xanthan Gum, Polyquaternium-51, Trehalose, Tocopheryl Acetate, Fragrance, Allantoin, Limonene, Potassium Sorbate, Sodium Benzoate, Ascorbyl Palmitate, Ceramide 2, Citric Acid, PEG-10 Rapeseed Sterol, Palmitoyl Oligopeptide, Tribehenin, Phenoxyethanol, Sodium Hyaluronate, Triacetin, Copper PCA, Hexyl Cinnamal, Benzoic Acid, Geraniol, Disodium EDTA.